Acute Myocarditis and Inflammatory Cardiomyopathies: Insights From Cardiac Magnetic Resonance Findings

Abstract

Myocardial inflammation encompasses a broad spectrum of conditions, including acute myocarditis, chronic inflammatory cardiomyopathy, and several overlapping entities that differ in clinical presentation, pathophysiology, and progression. These conditions range from self-limiting acute inflammation to chronic myocardial injury and dysfunction. The etiologic classification of myocardial inflammation highlights the complexity of its pathogenesis, involving direct tissue damage, immune-mediated mechanisms, and environmental triggers. Cardiac magnetic resonance (CMR) imaging has become a central diagnostic tool in the assessment of myocardial inflammation, providing precise characterization of myocardial tissue, assessing cardiac function, and stratifying prognosis. Advanced techniques such as T1 and T2 mapping and extracellular volume quantification have further expanded its diagnostic capabilities. This review highlights the essential role of CMR in diagnosing myocardial inflammation, recognizing various imaging findings associated with different underlying causes, and informing clinical management. The standardization of CMR protocols, along with advancements in imaging techniques and strengthened interdisciplinary collaboration, represents a fundamental step toward improving diagnostic accuracy, patient outcomes, and the understanding of the broad spectrum of myocardial inflammatory diseases.